MoveOnBoot

I use it fairly frequently - its been in my standard toolkit for years, and I've found it to be reasonably effective. While it may not always get the job done, it works in most cases not involving particularly nasty/tricky files. Bear in mind, anything you tell it to get rid of gets a one-way ticket outta town when it does work. Another app you might wanna consider is Optipon*Explicit's Pocket Killbox
Detailed tutorial HERE.

HiJackThis has a similar, and more or less equally capable, if slightly more fiddley feature in its "Miscelaneous Tools" section.

Sometimes, one will work where the others won't.

Thanks, timber. Will give 'em a try. Not that I would have a nasty old virus in my computer.